I've had the sigma 10-20 for a while and am happy for the most part but have found that below 14mm I have to bracket focus to guarantee edge to edge sharpness. I usually shoot at 6.3 or 8.0. Any suggestions or ideas to make this lens more consistent (I'd rather not shoot smaller than f8 since center sharpness starts to noticeably degrade). When its good its amazing but its annoying when a great landscape shot is ruined by side blurriness.

I run mine at f/11 usually. f/8 is sharp in the center but soft at the edges. I usually only use it at 10mm and have best results in portrait orientation (a lot harder to control perspective distortion in landscape).
There's a Flickr group that covers the 10-20...

easy,
set it at 10mm f8 manualy prefocus at 1m and shoot.
set like this you are on hyperfocal distance, so everything from roughly 0.5m to infinity is in zone of acceptable foucus. If shots won't be sharp you either have camera shake, bad techinque or faulty lens...
BR

how do you people compose for lenses like this?..the wider the lens gets the less use I have for it...I have only made two keeper shots from the Voigtlander 12mm f/5.6 heliar. I find it really hard to compose using super wide angle lenses.

the widest lens I find practical to use is no wider than 28mm. for 35mm and 1.5X format digital

how do you people compose for lenses like this?..the wider the lens gets the less use I have for it...I have only made two keeper shots from the Voigtlander 12mm f/5.6 heliar. I find it really hard to compose using super wide angle lenses.

the widest lens I find practical to use is no wider than 28mm. for 35mm and 1.5X format digital

they say something about pic being wort couple of words, so this is how:

how do you people compose for lenses like this?..the wider the lens gets the less use I have for it...I have only made two keeper shots from the Voigtlander 12mm f/5.6 heliar. I find it really hard to compose using super wide angle lenses.

the widest lens I find practical to use is no wider than 28mm. for 35mm and 1.5X format digital

It's great for getting up close to things and for indoors. That wide, and you are going to get widely exaggerated perspectives. I mainly use mine for getting up close to subjects and still having some background in the shot.

how do you people compose for lenses like this?..the wider the lens gets the less use I have for it...I have only made two keeper shots from the Voigtlander 12mm f/5.6 heliar. I find it really hard to compose using super wide angle lenses.

Ooh I loved the 10-20 back in using Nikon. I've still yet to get an UWA in Pentax. Still crossing fingers for an 11-16, and I'm pretty sure to get a DA15 someday.

Anyway on using it, it's really fun at first but it's quite hard to shoot efficiently with it. Few things you can do:

(1) Push in TIGHT. Go close. Real close. You're bound to get something interesting.
(2) When capturing a scene you need (A) foreground and (B) background. These 2 combined can make a really good shot. Perfect example is axl's photo with the guy on the street.
(3) Play with the relationship of the subject with the environment. The really cool thing about UWA lenses is that it can make something look REAL far away, you can add some real depth in a photo. Here are some examples:

(4) Don't be afraid to take portraits too! You can get some really interesting and unique ones with UWA lenses. Just be mindful of your angles to control the distortion on the subject

I love this. Where is it, and how did you get the columns exposed like that with the sun in the shot?

Thanks.

This was taken in India, and the sun is much kinder to the sensor. It was very difficult to blow the sky in India, where as here in the USA, even the mild sky blows out unless I underexpose the ground...so, it was just geography. I was surprised to see the sensor capture the reflections on the granite so well too....